The primary diagnostic radiographic imaging technology in current use combines a radiographic film with one or two intensifying screens. In a screen-film system, the film, generally placed between two phosphor screens, is exposed by the image forming radiation, then developed to provide a display image. This image can be viewed directly or digitized in a film digitizer that can be further processed, viewed on a monitor, or printed.
Another useful x-ray imaging technology utilizes a photostimulable storage phosphor on which the image is formed by the exposing radiation. This image is read out by a laser scanner, which produces an array of digital data that can be displayed on a monitor, subjected to further processing, or printed.
More recently, thin-film transistor (TFT) technology, involving the use of a pixel array of radiation sensors and associated field effect transistors, has been investigated for application to x-ray imaging. Although this technology currently suffers from some limitations of image resolution and display area, it has the significant advantage over screen-film and storage phosphor systems of providing an x-ray image with nearly real-time response.